In hydraulic or pneumatic installations for transporting fluids under pressure, a tight coupling of the rigid pipes to the different orifices of the installation equipment is generally accomplished by means of flanged connections. Such connections comprise a nut with an inner shoulder which engages the flanged end of a pipe. The shoulder is mounted on the pipe in a locking manner and can be screwed onto a threaded end forming an integral part of an equipment orifice. A gasket may be placed between the end of the pipe and the equipment to obtain a seal.
There are several methods for arranging a flange at the end of a pipe. The flange can, for example, be brazed onto the pipe end. To obtain a brazed joint of good quality, the flange and the pipe end must be cleaned. Such cleaning increases the time required to make the connection and increases the cost of the operation.
Another known method is to provide a hammered flange. Such flange is obtained by beating the pipe end which has previously been placed into a die by means of a range of gauged tools which makes it possible progressively to deform the pipe end until a flange is obtained.
Creating a flange in this manner can be time-consuming and costly.
French Patent reference No. FR 2 642 500 discloses a method for making a coupling according to which the pipe flange is realized by cold-flaring. This method for making a connection is fast and economical.
Machines exist for implementing this method, such as that disclosed in FR 2 660 219. These machines comprise two jaws forming a clamping device in which the pipe end to be coupled is placed, a forming die and means for giving the die an orbital motion.
U.S. Pat. No. 3,610,016 also discloses a machine for flaring the end of a pipe. This machine has a base on which is mounted, on one side, a stationary unit comprising two jaws for receiving the pipe to be flared and, on the other side, a mobile unit with translational motion in the direction of the jaws which comprises a tool and is moved by a mounted cylinder. The tool of this mobile unit is driven to rotate around an axis that is parallel to the axis of displacement of the mobile unit and thus executes a cylindrical movement. A motor disposed, for example, underneath the base of the machine, provides the power required for the machine's proper functioning.
European Patent reference No. EP 0 462 719 discloses a machine for flaring pipes by hot working. This machine is destined to be used for oil exploration below the sea. The machine comprises a base formed by two end plates which are connected by four parallel pipes, a mounted movable trolley running on the four pipes, a tool driven to rotate around an axis parallel to the pipes and mounted on the movable trolley, and means for holding the pipe to be flared in place as well as means for moving the trolley.
Due to the structure of these machines, the machines can be heavy, bulky and difficult to transport. Moreover, most of them do not permit an orbital movement of the tool. However, the erection of a hydraulic or pneumatic system often requires on-site pipe connections for some of the equipment of the system. These connections must then be ordered and fabricated at the factory, which can cause delays of several days.